PART 2 - THE FIVE STEPS OF FIRE RISK ASSESSMENT

For a fire to start, three things are needed:

a source of ignition;

fuel; and

oxygen.

If any one of these is missing, a fire cannot start. Taking steps to avoid the three coming together will therefore reduce the chances of a fire occurring.

FUEL Flammable gases Flammable liquids Flammable solids OXYGEN Always present in the air Additional sources from oxidising substances IGNITION SOURCE Hot surfaces Electrical equipment Static electricity Smoking/naked flames

Once a fire starts it can grow very quickly and spread from one source of fuel to another. As it grows, the amount of heat it gives off will increase and this can cause other fuels to self-ignite.

The following paragraphs advise on how to identify potential ignition sources, the materials that might fuel a fire and the oxygen supplies which will help it to burn.

You can identify the potential ignition sources in your workplace by looking for possible sources of heat which could get hot enough to ignite the material in the workplace. These sources of heat could include:

smokers' materials, eg cigarettes and matches;	Naked flame Hot surface Mechanically generated sparks Electrically generated sparks
naked flames;
electrical, gas or oil-fired heaters (fixed or portable);
hot processes (such as welding or grinding work);
cooking;
engines or boilers;
machinery;
faulty or misused electrical equipment;
lighting equipment, eg halogen lamps;
hot surfaces and obstruction of equipment ventilation, eg office equipment;
friction, eg from loose bearings or drive belts;
static electricity;
metal impact (such as metal tools striking each other); and
arson

Indications of 'near misses', such as scorch marks on furniture or fittings, discoloured or charred electrical plugs and sockets, cigarette burns etc, can help you identify hazards which you may not otherwise notice.

Anything that burns is fuel for a fire. So you need to look for the things that will burn reasonably easily and are in sufficient quantity to provide fuel for a fire or cause it to spread to another fuel source. Some of the most common 'fuels' found in workplaces are:

flammable liquid based products such as paints, varnish, thinners and adhesives;

flammable liquids and solvents such as petrol, white spirit, methylated spirit and paraffin;

flammable chemicals;

wood;

paper and card;

plastics, rubber and foam such as polystyrene and polyurethane, eg the foam used in upholstered furniture;

flammable gases such as liquefied petroleum gas (LPG) and acetylene;

furniture, including fixtures and fittings;

textiles;

loose packaging material; and

waste materials, in particular finely divided materials such as wood shavings, offcuts, dust, paper and textiles.

You should also consider the construction of your workplace and how this might contribute to the spread of fire. Does the internal construction include large areas of:

hardboard, chipboard, blockboard walls or ceilings; or

synthetic ceiling or wall coverings, such as polystyrene tiles?

If these are present, and you are uncertain of the danger they might pose, you should seek advice from your local fire authority or other experts on what precautions you need to take to reduce the risk to people in the event of fire.

The main source of oxygen for a fire is in the air around us. In an enclosed building this is provided by the ventilation system in use. This generally falls into one of two categories: natural airflow through doors, windows and other openings; or mechanical air conditioning systems and air handling systems. In many buildings there will be a combination of systems, which will be capable of introducing/extracting air to and from the building.

Additional sources of oxygen can sometimes be found in materials used or stored in a workplace such as:

some chemicals (oxidising materials), which can provide a fire with additional oxygen and so assist it to burn. These chemicals should be identified on their container by the manufacturer or supplier who can advise as to their safe use and storage; or

oxygen supplies from cylinder storage and piped systems, eg oxygen used in welding processes or for health care purposes.

If there is a fire, the main priority is to ensure that everyone reaches a place of safety quickly. Putting the fire out is secondary to this because the greatest danger from fire in a workplace is the spread of the fire, heat and smoke through it. If a workplace does not have adequate means of detecting and giving warning or means of escape, a fire can trap people or they may be overcome by the heat and smoke before they can evacuate.

As part of your assessment, you need to identify who may be at risk if there is a fire, how they will be warned and how they will escape. To do this you need to identify where you have people working, whether at permanent workstations or occasional ones, and to consider who else might be at risk, such as customers, visiting contractors etc, and where these people are likely to be found.

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